A heat exchanger known in the art includes a plurality of fins spaced apart such that gas (e.g., air) flows through spaces defined by the fins, and a plurality of heat transfer tubes through which a medium (e.g., refrigerant) flows and which extend through the fins.
A technique has been proposed to improve heat transfer performance of such a heat exchanger by optimizing a column pitch and a row pitch of the heat transfer tubes and arranging slits in the fins (refer to Patent Literature 1, for example).